Illuminating device.



H. ALEXANDER. ILLUMINATING DEVICE.

APPLICATION FILED JAN. 2, 1913.

L 1 $998 Eatented Feb. 23, 1915.

' W messe Inventor I Specification of Letters Patent.

ASSIGNOR IO-THE ALEXALITE COMPANY,

NEW YORK.

ILLUMINATING DEVICE.

rammed Feb. 23. 19115.

Application filed January 2, 1913. Serial No. 739,705.

To all'wliom'z'zt may concern:

Be it known that 1, HARRY ALEXANDER,

a citizen of the United States, residing-in the borough of .ll/lanhattan, city, county, and

State of New York, have invented a certain new and useful Illuminating Device, of which the following 18 a specification.

- This invention relates to devices for illuminating rooms, and other places, by indirect rays of light from incandescent electric lamps.

The objects of the invention are:- -First:

increased efficiency. Second: the avoidance of shadows and irregular illumination. Third: proper cooling of the fixture to prevent injury to the lamp. These and furthiir objects will more fully appear in the following specification and accompanying drawings, considered together or separately.

In the drawings: Figure 1 is a sectional view of a device embodying my invent-ion; and Fig. 2 is a plan view of the shield or diffuser.

In both of the views, like parts are designated by the same reference characters.

According to the preferred embodiment of my invention, I utilize a single, incandescent electric lamp of proper candle power, mounted in an inverted support and surrounded and shielded by an open, basinlike shield or diffuser, with a reflecting inside surface, which reflects the light upward against the ceiling, which, in turn, reflects and diffuses the light downward, without shadows or bright spots.

The lamp 1, may be of any shape, specifically as shown, or otherwise. It is carried in the socket 2, of any type, the latter being carried by the support 3. The support is connected to the ceiling 4r, which may be natural or artificial, as desired. A canopy 5 is shown at the upper end of the support 3, but this may be omitted, if desired.

The shield or diduser 6, is supported in proper relation to the lamp. It is open at the top, as shown, without any inset bead or ornamentation at the edge; hence, no shadows can be cast by the edge of the shade. A bead 7, forstrength and ornamentation, is shown on the outside of the edge, where itwill cast no shadow.

The shield is conveniently supported from the support 3 by means of a bracket 8, and chains 9. I prefer to make the bracket 8 as shown in Fig. 1. This bracket has arms which extend outward and downward on the sides of the socket 2. To the outer-ends of the arms are attached the chains 9. These chains constitute a means for supporting the shield or diffuser. The chains 9, as shown, are connected to the shield' at a place removed from the inner edge of the shield. This arrangement of the chains brings them within the zone of the reflected light rays and any shadows, of the chains, cast by the direct rays from the source of illumination will be intercepted by the rays reflected from the inner surface of the shield. This has the effect of preventing the chain from casting shadows. This is the preferred embodiment, but the chains may be attached to any other part of the shield. Instead of a chain, any other suitable supporting means may be employed. The inner surface of the shield is preferably enameled, or painted some light color. This I prefer to a. highly polished surface, for the reason that bright spots are not cast by it, as is the case with a highly polished reflector. I prefer it to a glass reflector, for the further reason that dust will not appreciably affect its eiiiciency to as great an extent.

I prefer to make the shield corrugated, as shown, the corrugations being in the form of concentric rings. This has the effect of diffusing the light, as it willbe reflected back and forth from side to side of the shield, due to the continually changing reflecting angle, finally issuing at an acute angle to the horizontal, and increasing the area of illumination of the ceiling.

For the purpose of increasing the reflecting effect of the shield, I locate the lamp in such a position in relation to the shield that its center of illumination is in, or approximately in, the focal point of the reflecting surface. To permit this to be done, it is necessary to distort the shape of the shield adjacent to the center, so that the bottom of the lamp will 'not come in contact with th shield, while at the sametime the filament of the lamp will be at the focal point of the reflecting surface. This is accomplished by. dropping the center of the shield to form a cup 10, of proper size so that the lamp may be lowered to such apoint that the teat on the lower end will ust avoid contact with the bottom of the cup.

I find that this lighting device is very eiiicient, partly owing to the use of a single lamp, and also partly due to the corrugations on the reflecting surface; The close it. For the purpose of ventilation, I provide a plurality of openings 11, inthe bottom of the cup. I prefer to group these openings around. the center of the'cup, as shoWn.- I find that a-single opening, in line With the center of the lamp, reduces the'eiiieiency-of f the apparatus, While four openings grouped as'sho'vvn, While having the same cross-sectional area of passage,'will not affect the efficiency to so great an extent.

- To prevent direct rays of light from passing downwardflilfi attach a cap 12 to the bottom of the cup' 10, at a suflicient distance to permit the ready entrance of air to the passages 11. The inside of the cup may have the same finish as the inside of the shield, so that raysof light escaping through the passages 11 will be reflected back. The cap 12 is supported upon a. stem 13, and secured in place by a. nut 14, as shown, so that it may be removed for cleaning. A further advantage'o'f-the cup 10 is that it permits the, lamp to be placed so low Within the shield that it will be'shielded, and no rays will.

issue'horizontally, and hence the lamp will not be directly visible. This is possible With a shield of comparatively small size, so proportioned as to secure the maximum diffusing and reflecting eiliciencyl The attachment of the chains 9 to the shieldat some distance from the inner edge of the latter, allows the raysof light to strike the chains from all directions, and shadows cast in one direction Will be dissipated by light rays striking the chains from anotherdirection; hence, no shadowswill be cast by the chains, upon the ceiling.

The feature of supporting the lampv from above, and independently of the shield, is

very important, as I utilize all of the area of the inside of the shield as a reflecting surface, which would not be the case if the lamp were supported from belo\v', and its support passed through the shield.

In accordance With the provisions of the patent statutes, I-have described the principle of my invention, together with the apparatus which I now consider to represent the best embodiment thereof; but I desire to have it understood that the apparatus shown is merely illustrative, and that the invention may be carried out in other ways.

Having now described my invention, What I claim as new and desire to secure by Letters Pa 1 is:--

l. A: lnminating device which comprises, in combination, a reversed socket supporting an incandescent electric lamp, a

support for the socket, an opaque diffusing shield surrounding the lamp at the sides and below and having a reflecting inner surface, I "said sh eld being open at. the top, and means connecting the support and shield, such porting an incandescent electric lamp, a support for the, socket, an opaque diffusing shield'surrounding the lamp at the sides and below and having a reflecting inner surface,

- said shield being open at the top, and means connecting the support and shield, suchmeans being connected to the shield within the zone of, the reflected light rays and to the support above the socket.

3; An illuminating device Which comprises, in combination, a'revers ed socket supporting an incandescent electric lamp, :1 support for the socket, an opaque diffusing shieldsurrounding the lamp at the sides and below, and having a reflecting inner surface, said shield being open at the top, and means connecting the support and shield, such means being connected to the shield inside the outer edge thereof and to the supportabove the socket.

4. Anilluminating device, comprising, in combination, a reversed incandescent electric lamp socket, alamp, a support therefor,

an opaque shield or difl'user surrounding the lamp at the sides and below and having a reflecting inner surface, said shield being open at the top, a bracket carried by the support above the. socket and having arms which-extend out on each side of the socket,

and means connecting the ends of the arms with the shield, such means being connected to the shield ivithin the zone of the reflected light rays 5, An iilT-minating 'device' which (10171" prises, in combination, a reversed source of illumination and a support therefor, an opaque bowl having a reflecting inner surface supported in such a manner as to' conceal the lamp from the sides and from below, concentric corrugations in the bowl to reflect and vre-reflect the light rays, and supports for the bowl, said supports being connected to the bowl within the zone of the reflected light rays.

This specification signed and witnessed this 31st day of Dec, 1912.

HARRY ALEXANDER. 

